Means for proportioning pull to specimen size



Jan. 10, 1950 D. c. SCOTT MEANS FOR PROPORTIONING PULL TO SPECIMEN SIZE Filed July 16, 1945 a 'a g fs z/ a V] I 60 Murm ATTORNEYS Patented Jan. 10, 1950 FQR-BROPORTIONING PULL .TO PEQIM SIZE David C. Scott, Providence, VR. 1.,

assignor Ito Henr'y LL Scott Gompany, a corporation of Ith-ode Island a puc n mm y 1 .1945, Serial No. 305,339

Thisdeyice. relates-to a testing machine, more particularly of the'in'clined plane type.

In order that comparative, tests may be provided in a testing machine uniform specimens mustbeprovided. For "instance;' in comparing tests on rubber threads, specimen threadsof a uniform cross;sectional;dimg i sifin'must be had. If specimens of non-uniform dimension are teste,d, then-sonre compensa onj'must be made by cjalculationiii, "comparative curves for graphs are are -provi ect-"- zon s: hqi i r de a tQestspeci smay be used-i machinesangi 'ggt coinparative" results will be indicated directly-"on the platenor'reeordirigmans as the tests are made with no mathematical computation necessary to reduce the test data to a uniform standard.

Another object of this invention is to adjust the pull which is applied to the specimen so as to cause this pull to be proportional to the cross section of the specimen according to a predetermined schedule.

Another object of this invention is to provide an easily manually adjustable weight applying means to provide the proper mass.

With these and other objects in view, the invention consists of certain novel features of construction, as will be more fully described and particularly pointed out in the appended claim.

In the accompanying drawings:

Fig. 1 is an elevation of a testing machine equipped with this invention;

Fig. 2 is a perspective view of the carriage which applies the pull to the specimen;

Fig. 3 is a perspective view of one of the weights which is assembled with the carriage; and

Fig. 4 is a perspective view of a different weight which is assembled with the carriage.

In proceeding with this invention I utilize the inclined plane type of testing machine which has heretofore been known, and provide a new form of carriage therefor which is equipped with a plurality of weights which may be readily manually removed that the proper carriage mass may be had. In this manner I may cause the weight of the carriage which applies tension to the specimen to be adjusted in accordance with the cross sectional dimension of the specimen according to a predetermined calculation and thus the record which is mechanically formed in the machine will be comparative for all specimens even though they be of varying cross sectional dimensions.

With reference to the drawing in designates a oft-his invention is to prons-i, so that differ nt cross sectional I12 at. theupper endjof this standard H a,

clinabiebeam desi nated g ner lly];-

The beam; l3, provided. with tour rollers 14.,

L5; 4.6. a d llwhich aregrooved. to'r sir and.

lidablylmount a pla aclamp [3 for. p siti n thereo -j A. platen lchas a. flexible efle which element extends ably'mounted n23 meri 'isancbored "to, s m- .In thisma'rlner ts piv .12 he-Ph the e Lm'by; lid on; "The" beam l3 h' which rests upon a horizontal support 21 from which extends a rack 28 which engages with a pinion so that the same will be lowered in response to the operation of a motor 29 operating through gears in box 30 and controlled as to reversing by the handle 3| and as to operation by the clutch handle 32.

The beam also carries a track 25 on which is mounted a specimen clamp 33 operated through an eccentric 34 having handle 35 so as to grip a specimen 36 and hold it in fixed relation to the beam. Also mounted on this track is a carriage designated generally 31, which has a pair of wheels 38 and 39 resting on the track with axles extending into the bearings 40 and 4| for the wheel 39 and 42 and 43 for the wheel 38. The carriage has an end plate 44 upon which a specimen clamp 45 having eccentric 46 and handle 41 is mounted for clamping the other end of specimen 36. Depending from the framework 48 in which the bearings 40 to 43 are provided, there is a frame 49 of generally rectangular shape having end walls 5|) and 5|, a top wall 52 and a bottom wall 53 with intermediate shelves 54 and 55. On the three shelves 53, 54, and 55 I provide a plurality of weights 56. Three weights may be positioned on each of the shelves such as indicated in Fig. 1, the handle portion 51 serves as a convenient means for removing the weights from the shelves as desired. A supporting rod 58 extends downwardly from the frame 43 and then horizontally as at 59 to support weights 6|] by means of openings 6| therein. Weights to are in a number sufficient to supply weight to the carriage in fractional amounts of the weight 55. Thus, by means of a plurality of weights 56 and an the desired mass may be provided for the carriage 31 so as to adjust its weight is which is provided with jlik according to the cross sectional dimension of the specimen to be tested in accordance with a predetermined calculation which may be worked out for each type of material or specimen to be tested. The weight 60 may be of difierent values as shown at 68a, 60b, and 600, Fig. 1.

In orderto compensate or counterweight for the mass of the beam, at the left-hand side of the pivot I2, I provide a rod 65 having a weight 66 thereon which may be positioned along the rod 65 in varyin distances from the pivot to be then held in position by theset screw 61.

In the testing of rubber thread the cross sectional area of the thread to be tested is usually measured in square mills. The weight of the carriage alone without any weights 56 or 50 will be calculated for the smallest square mill area of a specimen which is likely to be provided for testing. Should the square mill area of the specimen tested be greater than this smallest;

area then additional weights will be required on the carriage, where this smallest area is to be the standard of comparison. The carriage is usually 100 grams. The weights 56 and 60 are usually marked in square mills and the arrangement is such that if the area of the specimens to be tested is 45 square mills greater than the standard of comparison then weights marked to 45 square mills will be placed upon the carriage in addition to its weight. Such U weights 56 and 60 which Will figure up to 45 square mills will be placed on the shelves or hung upon the hook 59. If 54 square mills was the area of the specimen to be tested, then in addition to the 45 square mills, 9 additional square mills will be used by selecting weights such as 60a or 6012 marked according to a predetermined beam, a clamp carried by the beam for securiing one end of a specimen, a carriage movable along the beam as the same is inclined, means for securing the other end of a specimen to said carriage, said carriage comprising a plurality of separate superimposed open-ended compartments for the reception of weights and separable weights for said compartments to adjust the effective mass of the carriage.

REFERENCES CITED The following references are of record file of this patent:

UNITED STATES PATENTS Number Name Date 575,143 Prough Jan. 12, 1897 920,942 Fleming May 11, 1909 1,008,308 Brierclifl'e Nov. 14, 1911 1,674,971 Hutchinson June 26, 1928,

2,205,579 Scott. June 25, 1940 2,286,651 Scott; June 16., 1942 DAVID C. sco'r'n in the Wallace g. June 15, 1943; 

